Good news, on the iPhone 6 HDR isn't necessary on the front camera. See quote from the User Guide.
“HDR
HDR (High Dynamic Range) helps you get great shots, even in high-contrast situations. The best parts of three quick shots, taken at different exposures (long, normal, and short), are blended together into a single photo.
Note: On iPhone 6 and iPhone 6 Plus, the FaceTime camera creates high dynamic range photos using the camera’s sensor, instead of blending three separate shots. This feature is always on, and only one photo is created (which is not labeled HDR).”
Excerpt From: Apple Inc. “iPhone User Guide For iOS 8.” Apple Inc., 2014. iBooks.
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